Two analysis examples on NFT and Helium
Thomas de Marchin
14DEC2022
Several Tb of data
Data are stored sequentially, requires developing specific tools to follow a transaction.
The structure of a transaction is difficult to read
Fragmentation of blockchain technologies
Two examples implemented in R:
OpenSea: big NFT market place
Weird Whales: collection of 3350 whales programmatically generated, each with their unique characteristics and traits. Created by a 12-year-old programmer named Benyamin Ahmed who made the buzz.
EtherScan: block explorer to view information about transactions, verify contract code, visualize network data -> access to more raw data
Weird Whales are managed by a specific smart contract on the Ethereum blockchain
To make it easier to extract information from the blockchain, we can read the events: dispatched signals the smart contracts can fire.
resEventTransfer <- GET("https://api.etherscan.io/api",
query = list(module = "logs",
action = "getLogs",
fromBlock = fromBlock,
toBlock = "latest",
address = "0x96ed81c7f4406eff359e27bff6325dc3c9e042bd",
topic0 = "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
apikey = EtherScanAPIToken)) Wait… Where is the sales price? On OpenSea, sales are managed by the main contract and if approved, the second contract is called (here Weird Whales), which then triggers the transfer. Need to download all the transactions from the OpenSea main smart contract address and then filter for the ones related to Weird Whales (can take several hours…).
Ethereum / USD rate is highly volatile, need to download the historical ETH USD price if we want to convert ETH to USD:
Networks are described by vertices (or nodes) and edges (or links). Here we are going to use a node representation for a wallet address. The network we are going to construct will display all the wallet addresses that have ever traded Weird Whales. The connections between the vertices, so called edges, will represent the transactions.
network and ggraph packages
network and networkDynamic packages
Helium is a decentralized wireless infrastructure for IoT devices (environmental sensors, localisation sensors to track bike fleets,…). It is a blockchain that leverages a decentralized global network of Hotspots. People are incentivized to install hotspots and become a part of the network by earning Helium tokens, which can be bought and sold like any other cryptocurrency.